老师，有个地方没理解

NO.PZ2016082404000024问题如下 You have a portfolio of US5 million to heeusing inx futures. The correlation coefficient between the portfolio anfutures being useis 0.65. The stanrviation of the portfolio is 7% anthof the heing instrument is 6%. The futures priof the inx futures is US1,500 anone contrasize is 100 futures. Among the following positions, whione reces risk the most?   Long 33 futures contracts   Short 33 futures contracts   Long 25 futures contracts   Short 25 futures contracts ANSWER: o hee, the portfolio manager shoulsell inx futures, to create a profit if the portfolio loses value. The portfolio beta is 0.65×7%6%=0.758.0.65\times\frac{7\%}{6\%}=0.758.0.65×6%7%​=0.758.The number of contracts is N∗=−βSF=−(0.758×5,000,000)1,500×100=−25.3N\ast\text{=}-\beta\frSF=\frac{-{(0.758\times5,000,000)}}{1,500\times100}\text{=}-25.3N∗=−βFS​=1,500×100−(0.758×5,000,000)​=−25.3 or 25 contracts.5mx1+0.758*150000*Nf=0，这才是正确的公式啊

NO.PZ2016082404000024问题如下 You have a portfolio of US5 million to heeusing inx futures. The correlation coefficient between the portfolio anfutures being useis 0.65. The stanrviation of the portfolio is 7% anthof the heing instrument is 6%. The futures priof the inx futures is US1,500 anone contrasize is 100 futures. Among the following positions, whione reces risk the most?   Long 33 futures contracts   Short 33 futures contracts   Long 25 futures contracts   Short 25 futures contracts ANSWER: o hee, the portfolio manager shoulsell inx futures, to create a profit if the portfolio loses value. The portfolio beta is 0.65×7%6%=0.758.0.65\times\frac{7\%}{6\%}=0.758.0.65×6%7%​=0.758.The number of contracts is N∗=−βSF=−(0.758×5,000,000)1,500×100=−25.3N\ast\text{=}-\beta\frSF=\frac{-{(0.758\times5,000,000)}}{1,500\times100}\text{=}-25.3N∗=−βFS​=1,500×100−(0.758×5,000,000)​=−25.3 or 25 contracts.这里公式直接负贝塔，是因为目标贝塔为0，贝塔*是0，所以直接代公式看结果正负就行了，这么理解对吗？

NO.PZ2016082404000024 问题如下 You have a portfolio of US5 million to heeusing inx futures. The correlation coefficient between the portfolio anfutures being useis 0.65. The stanrviation of the portfolio is 7% anthof the heing instrument is 6%. The futures priof the inx futures is US1,500 anone contrasize is 100 futures. Among the following positions, whione reces risk the most?   Long 33 futures contracts   Short 33 futures contracts   Long 25 futures contracts   Short 25 futures contracts ANSWER: o hee, the portfolio manager shoulsell inx futures, to create a profit if the portfolio loses value. The portfolio beta is 0.65×7%6%=0.758.0.65\times\frac{7\%}{6\%}=0.758.0.65×6%7%​=0.758.The number of contracts is N∗=−βSF=−(0.758×5,000,000)1,500×100=−25.3N\ast\text{=}-\beta\frSF=\frac{-{(0.758\times5,000,000)}}{1,500\times100}\text{=}-25.3N∗=−βFS​=1,500×100−(0.758×5,000,000)​=−25.3 or 25 contracts. The futures priof the inx futures is US1,500 anone contrasize is 100 futures中one contrasize is 100 futures是指的一份 inx futures中包含100个小的futures吗？就是那个乘数是吗？

NO.PZ2016082404000024 You have a portfolio of US5 million to heeusing inx futures. The correlation coefficient between the portfolio anfutures being useis 0.65. The stanrviation of the portfolio is 7% anthof the heing instrument is 6%. The futures priof the inx futures is US1,500 anone contrasize is 100 futures. Among the following positions, whione reces risk the most?   Long 33 futures contracts   Short 33 futures contracts   Long 25 futures contracts   Short 25 futures contracts ANSWER: To hee, the portfolio manager shoulsell inx futures, to create a profit if the portfolio loses value. The portfolio beta is 0.65×7%6%=0.758.0.65\times\frac{7\%}{6\%}=0.758.0.65×6%7%​=0.758.The number of contracts is N∗=−βSF=−(0.758×5,000,000)1,500×100=−25.3N\ast\text{=}-\beta\frSF=\frac{-{(0.758\times5,000,000)}}{1,500\times100}\text{=}-25.3N∗=−βFS​=1,500×100−(0.758×5,000,000)​=−25.3 or 25 contracts. 老师讲了N>0应该是long，不知道这么理解对不对